# A180143 (b-file synthesized from sequence entry)
0 1
1 4
2 16
3 58
4 208
5 742
6 2644
7 9418
8 33544
9 119470
10 425500
11 1515442
12 5397328
13 19222870
14 68463268
15 243835546
16 868433176
17 3092970622
18 11015778220
19 39233275906
20 139731384160
21 497660704294
22 1772444881204
23 6312656052202